Sealed electric compressors (referred to as compressors hereinafter) designed for emitting small operating noise have been modified to reduce noise generated in its interior as being demanded worldwide.
A conventional compressor will be explained referring to the relevant drawings.
The conventional compressor is illustrated in FIGS. 5 and 6. A motor element 53 is provided over a compression element 52 elastically supported in an enclosure container 51. A crank shaft 54 is driven by the motor element 53 for rotating motions, and is joined at the lowermost end to an oil pickup tube 55. The enclosure container 51 accommodates an amount of refrigerator lubricant oil 56 for the compression element loaded therein.
An operation of the conventional compressor having the above arrangement will be explained.
The oil pickup tube 55 includes a centrifugal pumping portion 55a joined to the lowermost end of the crank shaft 54 rotating with the motor element 53 and a concentric spinning portion 55b arranged continuously of the centrifugal pumping portion 55a. When the tube 55 is driven, the concentric spinning portion 55b only spins in the refrigerator lubricant oil 56 in the enclosure container 51. This reduces a resonance noise generated with the oil pickup tube 55 which vibrates across the oil level during the spinning.
However, since the concentric spinning portion 55b spins in the refrigerator lubricant oil 56 in the enclosure container 51, the portion 55b generates a little centrifugal force at the opening end 61. The little force keeps a lifting stroke low, thus decreasing a the pumping amount of the lubricant oil.